Portunoidea
Guides
Carcinus
Green crabs
Carcinus is a genus of crabs in the family Carcinidae, comprising two recognized species: C. maenas (the European green crab or shore crab) and C. aestuarii (the Mediterranean shore crab). The genus is notable for containing one of the world's most successful marine invasive species, C. maenas, which has established populations across temperate coastlines on multiple continents. Both species share similar ecological roles as opportunistic predators in coastal marine systems. C. aestuarii is endemic to the Mediterranean Sea and has been implicated in at least one invasion event in Japan.